Эффективность функционирования системы проката автомобилей в Крыму

Целью статьи является исследование роли проката автомобилей в развитии автомобильного туризма, анализ рынка проката в Крыму, определение проблем и направлений развития системы автопроката в Крыму

Who are the job seekers? explaining unemployment among doctoral recipients

Despite increased attention for doctoral education in recent years, one particular phenomenon has received little attention—the unemployment of doctoral candidates following graduation. While the unemployment of doctoral recipients is relatively low in comparison to the general popula-tion, the absence of empirical studies means possible important patterns are being overlooked. Using survey data from four universities in the Netherlands, we investigate unemployment among recent doctoral graduates. By comparing the job seekers to employed doctoral recipients and fo-cusing on both structural and individual level variables, including demographic characteristics, previous research experience, job seeking activities, and differences in the PhD trajectory, we are able to discern a number of shared characteristics among the job seekers. Our findings suggest that unemployment among doctoral candidates is not random or evenly distributed. In contrast to the general population, where socio structural characteristics such as educational level and gender are integral in explaining unemployment, within this level of educational attainment primarily individual level factors are more salient in explaining unemployment among this group of job seekers

Moving Beyond Traditional Null Hypothesis Testing: Evaluating Expectations Directly

This mini-review illustrates that testing the traditional null hypothesis is not always the appropriate strategy. Half in jest, we discuss Aristotle's scientific investigations into the shape of the earth in the context of evaluating the traditional null hypothesis. We conclude that Aristotle was actually interested in evaluating informative hypotheses. In contemporary science the situation is not much different. That is, many researchers have no particular interest in the traditional null hypothesis. More can be learned from data by evaluating specific expectations, or so-called informative hypotheses, than by testing the traditional null hypothesis. These informative hypotheses will be introduced while providing an overview of the literature on evaluating informative hypothesis

Development and Evaluation of a Digital Expert Elicitation Method Aimed at Fostering Elementary School Teachers' Diagnostic Competence

Expert elicitation—an approach to systematically consult experts and quantify their insights—has been succesfully applied in fields as risk assessment, health and environmental research. Unfortunately, it has never been used within the Educational sciences, while it offers ample opportunities for educational practice, especially when used to foster the accuracy of teacher judgments; generally referred to as their “diagnostic competence.” The current paper is the first to explore expert elicitation in an educational context and has two major goals. The first goal is to develop a digital expert elicitation method suitable to be used by elementary school teachers for self-reflection purposes. The second goal is to extensively test the expert elicitation method, using a test panel of 24 primary school teachers for 503 pupils in total. Results regarding the development of the elicitation method and its reliability, construct validity, face validity and feasibility are discussed as well as ideas how this elicitation method can be a valuable self-reflection instrument for teachers. The results are promising: all measures of reliability, feasibility, face validity and construct validity show positive results and teachers are enthusiastic about the possibilities of the method

Illustrating Bayesian Evaluation of Informative Hypotheses for Regression Models

In the present article we illustrate a Bayesian method of evaluating informative hypotheses for regression models. Our main aim is to make this method accessible to psychological researchers without a mathematical or Bayesian background. The use of informative hypotheses is illustrated using two datasets from psychological research. In addition, we analyze generated datasets with manipulated differences in effect size to investigate how Bayesian hypothesis evaluation performs when the magnitude of an effect changes. After reading this article the reader is able to evaluate his or her own informative hypotheses

A Comparison of the Single, Conditional and Person-Specific Standard Error of Measurement: What do They Measure and When to Use Them?

Tests based on the Classical Test Theory often use the standard error of measurement (SEm) as an expression of (un)certainty in test results. Although by convention a single SEm is calculated for all examinees, it is also possible to (1) estimate a person-specific SEm for every examinee separately or (2) a conditional SEm for groups of comparable examinees. The choice for either of these SEms depends on their underlying assumptions and the trade-off between their unbiasedness and estimation variance. These underlying assumptions are discussed in the present article, together with a mathematical expression of the bias and estimation variance of each of the SEms. Using a simulation study, we furthermore show how characteristics of the test situation (i.e., test length, number of items, number of parallel test parts, overall reliability, relationship between “true” score and true (un)certainty in test results and rounding/truncation) influence the SEm-estimates and impact our choice for one of the SEms. Following the results of the simulation study, especially rounding appears to hugely affect the person-specific and—to a lesser extent—the conditional SEm. Therefore, when a test is small and an examinee is only tested once or a few times, it is safer to opt for a single SEm. Overall, a conditional SEm based on coarse grouping appears to be a suitable compromise between a stable, but strict estimate (like the single SEm) and a lenient, but highly variable estimate (like the person-specific SEm). More practical recommendations can be found at the end of the article

The Data Representativeness Criterion: Predicting the Performance of Supervised Classification Based on Data Set Similarity

In a broad range of fields it may be desirable to reuse a supervised classification algorithm and apply it to a new data set. However, generalization of such an algorithm and thus achieving a similar classification performance is only possible when the training data used to build the algorithm is similar to new unseen data one wishes to apply it to. It is often unknown in advance how an algorithm will perform on new unseen data, being a crucial reason for not deploying an algorithm at all. Therefore, tools are needed to measure the similarity of data sets. In this paper, we propose the Data Representativeness Criterion (DRC) to determine how representative a training data set is of a new unseen data set. We present a proof of principle, to see whether the DRC can quantify the similarity of data sets and whether the DRC relates to the performance of a supervised classification algorithm. We compared a number of magnetic resonance imaging (MRI) data sets, ranging from subtle to severe difference is acquisition parameters. Results indicate that, based on the similarity of data sets, the DRC is able to give an indication as to when the performance of a supervised classifier decreases. The strictness of the DRC can be set by the user, depending on what one considers to be an acceptable underperformance.Comment: 12 pages, 6 figure

Блокаторы рецепторов к ангиотензину II: имеются ли основания для широкого применения?

Представлен анализ эффективности и безопасности лечения блокаторами рецепторов к ангиотензину II на основании исследований последнего десятилетия по литературным данным. Отдельно рассмотрены проблемы возможного влияния этих препаратов на риск развития рака и инфаркта миокарда.Представлено аналіз ефективності та безпечності лікування блокаторами рецепторів до ангіотензину II на основі досліджень останнього десятиріччя за літературними даними. Окремо розглянуто проблеми можливого впливу цих препаратів на ризик розвитку раку та інфаркту міокарда.The efficacy and safety of treatment with angiotensin II receptor blockers is presented based on investigations of the recent decade was analyzed using the literature data. The problems of possible influence of these drugs on the risk of cancer development and myocardium infarction development are discussed

Direct aggression and generalized anxiety in adolescence:Heterogeneity in development and intra-individual change

Co-occurrence of aggression and anxiety might change during adolescence, or stay stable. We studied change and stability of four types of co-occurrence regarding direct aggression and anxiety in adolescence: an anxious and non-aggressive type, an aggressive and non-anxious type, a comorbid aggressive-anxious type and a no problems type. We applied a person-centered approach to assess increases and decreases of these types, and tested various models of intra-individual change of the types: the stability, acting out and failure models. We used data from a five-wave study of 923 early-to-middle and 390 middle-to-late adolescents (48.5 % male), thereby covering the ages of 12–20. We observed accelerated development in the older cohort: adolescents tended to grow faster out of the aggressive types in middle-to-late adolescence than in early-to-middle adolescence. We observed one other group-dependent pattern of heterogeneity in development, namely “gender differentiation”: gender differences in aggression and generalized anxiety became stronger over time. We found support for two perspectives on intra-individual change of the four types, namely the stability and the acting out perspective. The no problems—and to a lesser extent the anxious—type proved to be stable across time. Acting out was found in early-to-middle adolescents, males, and adolescents with poorer-quality friendships. In all three groups, there were substantial transitions from the anxious type to the aggressive type during 4 years (between 20 and 41 %). Remarkably, acting out was most prevalent in subgroups that, generally speaking, are more vulnerable for aggressive behavior, namely early-to-middle adolescents and males. We interpret acting out as the attempt of adolescents to switch from anxiety to instrumental aggression, in order to become more visible and obtain an autonomous position in the adolescent world. Acting out contributed to the explanation of accelerated development and gender differentiation. We also observed an increase of adolescents with no problems. These findings highlight that the co-occurrence of aggression and anxiety changes considerably during adolescence, but also that the anxious and no problems types are quite stable in this period. Keywords: Direct aggression Generalized anxiety Adolescence Longitudinal researc